Big Idea:
Understanding solids and nets helps develop the concepts of volume and surface area

Students will be writing in their notes what they feel is the difference between 2-D and 3-D objects. They are instructed to use drawings and examples to help explain the difference. I chose to do this because I wanted to assess prior understanding or hook them in for today’s learning. I’m going to give students some time to write and think about 2-D vs 3-D objects. Students can then pair up to discuss their thoughts on the subject.

Resources (3)

Resources

I will be discussing the vocabulary of three dimensional objects. This vocabulary is important because they will need to identify prisms and pyramids by their faces, bases, edges, and vertices. Once we go over the vocabulary we will be doing some practice at identifying the solids by these features. We will also be looking at their nets to help us see the characteristics easier.

Resources (1)

Resources

In this section we will be focusing on prisms. The students need to know that a prism has 2 parallel bases, it’s named by its base and the faces are made up of rectangles. Students have difficulty understanding the difference between a face and a base. Tell students that when they identify a prism, they should look for the two polygons that are the same. This will tell you the name of the prism. The net is useful here because they can actually see the 2 bases and the rectangular bases. It is also easier to count the edges and vertices in the net, but I would show them how to do it with the solid too. For each example, I would ask the student how the solid got its name? They should be able to point out that they see 2 polygons that are the same and it is named by these two polygons.

We will also be looking at a cylinder which is a special type of prism. Ask students why this can’t be classified as a prism and why it can? They should say that it does have 2 parallel bases , but it does not have rectangular faces.

Resources (1)

Resources

In this section, I will be talking with the students about pyramids. It is important for them to know that a pyramid has 1 base and triangular faces. A pyramid is also named by its base. For each example, there is a visual of the solid and the net to help with the explanation. Again, we will be looking at the edges, vertices, faces and bases. Continue to ask the students how the solid got its name. The hardest pyramids for students to understand are the difference between a triangular pyramid and a rectangular pyramid. They struggle with this because of the triangular sides. It’s important for students to see there is 1 rectangular base and the faces are triangles in a rectangular pyramid whereas, the triangular pyramid is made up of all triangles.

We will also be looking at a cone which is a special type of pyramid. The cone has 1 circular base. Some students may also see that the there is one vertex. Ask students why this can’t be classified as a pyramid and why it can? Students should say that it does have one base, but it is missing the triangular faces. They can also say that it is a pyramid because it does meet at one vertex.

Resources (1)

Resources

Allow students time to work on the 8 independent practice problems. These are in their notes. Go over this as a whole group so students can make changes as needed. As you work through each problem, they will be required to explain how they know their answer is correct. Having students support their decisions is implementing SMP3. As students finish the problems, they can do a HUSUPU to find a partner to share their solutions.

Similar Lessons

Big Idea:
Students explore cube nets in an effort to understand what properties are common to all nets that form a cube. Students work hands-on with nets and are then pushed to use their experience to visually determine whether other nets will form a given figures.